1. Field of the Invention
The present invention relates to a semiconductor device and method of manufacture thereof, circuit board, and electronic instrument.
2. Description of Related Art
With the increasingly compact nature of electronic instruments, semiconductor devices are known with a stacked construction incorporating a plurality of substrates (interposers) on which semiconductor chips are mounted laminated at high density. By means of this, the area of the circuit board (motherboard) on which the semiconductor devices are mounted is utilized efficiently, and an electronic instrument which is more compact and of high density can be manufactured.
For example, in Japanese Patent Application Laid-Open No. 8-236694, in a semiconductor device of stacked construction, connector terminals connecting upper and lower semiconductor chips are disposed on the extremity of a substrate to avoid a semiconductor chip disposed in a central portion. Then the circuit board and semiconductor device of stacked construction are electrically connected by connector terminals provided at the extremity of the substrate, in the same way that upper and lower semiconductor chips are connected.
However, according to this form of connection of the semiconductor device to the circuit board, since the pitch of the terminals for connection of the semiconductor device to the circuit board is fine, an expensive circuit board fine interconnecting lines must be used. By means of this, it is difficult to position the semiconductor device on the circuit board, and because of this the yield when the semiconductor device is mounted may be reduced.
Furthermore, since the connector terminals disposed at the extremity of the substrate are formed outside the semiconductor chip, if the pitch of the connector terminals is increased, there is a problem in that the area of the circuit board occupied by the semiconductor device also increases.